President Donald Trump's tax and policy bill could slow Arizona's clean energy industry, but companies aren't talking.

A $309M federal contract revives border wall construction in Arizona, sparking backlash from environmental groups and renewed ...

Earlier this week, the Star interviewed longtime Arizona Sierra Club leader Sandy Bahr on her view that the proposed Colorado River drought contingency plan legislation for Arizona is a pathway to ...

TEMPE – A night that was years in the making came to a head when Arizona State University’s women’s flag football club made its collegiate debut Jan. 31. For Sierra and Sophia Smith, game ...

The news comes amid a larger fight over what the transition to cleaner energy should look like — or if there should be a move ...

Prominent U.S environmental organization Sierra Club Foundation said it will move $10.5 million away from BlackRock because ...

Sierra Club Foundation announced it will terminate BlackRock as an asset manager for its $167 million in assets for failing ...

He thought a turning point for public concern about ocean pollution came when the county enacted more strict water testing, resulting in Imperial Beach beaches being closed virtually every day.

The Idaho chapter of the Sierra Club is organizing an "emergency picket" tonight to advocate for the preservation of public ...

BOISE — Idaho's Republican U.S. senators, Mike Crapo and Jim Risch, have voiced opposition to their Utah colleague Mike Lee's ...

The Sierra Club's filings argue that Basin should have retired at least three of the units at its coal-fired power plants by 2020, exited the lease for another unit in 2021 and begun to plan for ...